Enhancement mode transceiver and switched gain amplifier integrated circuit

An RF switched attenuator, comprising:

• a first control input;
• first and second control nodes;
• an inverter having an input coupled to first control input and to the second control node and an output coupled to the first control node;
• first and second capacitances, wherein the first capacitance has first and second terminals and the second capacitance has third and fourth terminals;
• first and second serially coupled resistances with a common connection node therebetween, wherein a combination of the first and second serially coupled resistances has fifth and sixth terminals;
• serially coupled third capacitance and third resistance, wherein a combination of the serially coupled third capacitance and third resistance have seventh and eighth terminals;
• first and second RF signal I/O ports, coupled respectively to the first and third terminals;
• a reference potential connection coupled to the eighth terminal;
• a first enhancement mode multi-gate FET device having source, drain and gate terminals, wherein its source is coupled to the second and fifth terminals, its drain is coupled to the fourth and sixth terminals and its gates are coupled to the first control node;
• and
• a second enhancement mode multi-gate FET device having source, drain and gate terminals, wherein its drain terminal is coupled to the common connection node and its source terminal is coupled to the seventh terminal, and its gates are coupled to the second control node.

A monolithic integrated circuit transceiver having an antenna RF I/O port configured to send an RF signal to or receive an RF signal from an antenna, an another frequency output port and an RF signal input port, wherein the transceiver comprises:

• a transmit-receive switch (T/R SW) having the antenna RF I/O port and first and second further ports, configured to couple the antenna RF I/O port to either the first or second further ports in response to first or second signals received at one or more control ports;
• a first amplifier having a first amplifier input port coupled to the first further port of the T/R SW, and having a first amplifier output port, wherein the first amplifier is configured to receive an RF signal from the antenna RF I/O port of the T/R SW and deliver an amplified RF signal thereof to the first amplifier output port;
• a frequency shifting apparatus having a first shifter input port coupled to the first amplifier output port and configured to receive the amplified RF signal from the first amplifier and provide a signal at a different frequency to the another frequency output port of the transceiver;
• a second amplifier having a second amplifier input coupled to the RF signal input port of the transceiver and having a second amplifier output coupled to the second further port of the T/R SW and configured to receive a input signal from the RF signal input port of the transceiver and provide an amplified version thereof to the T/R SW;
• and
• wherein the T/R SW, is configured so that in response to a first control signal received from the one or more control ports, it passes the signal received from the antenna RF I/O port to the first amplifier, and in response to a second control signal received from the one or more control ports, it passes the signal received from the second amplifier to the antenna RF I/O port;
• wherein the T/R SW comprises:
• first and second n-channel enhancement mode FETs, each having source, drain and multiple parallel-coupled gate regions serially arranged and spaced apart between the source and drain;
• wherein the sources of the first and second FETs are coupled to the antenna RF I/O port and the drain of the first FET is coupled to the first further port of the T/R SW and the drain of the second FET is coupled to the second further port of the T/R SW and the multiple parallel-coupled gate regions of the first FET are coupled to a first of the one or more control ports and the multiple parallel-coupled gate regions of the second FET are coupled to a second of the one or more control ports.